function getWindowHeight() {
    var windowHeight=0;
    if (typeof(window.innerHeight)=='number') {
        windowHeight=window.innerHeight;
    }
    else {
        if (document.documentElement && document.documentElement.clientHeight) {
            windowHeight= document.documentElement.clientHeight;
        }
        else {
            if (document.body && document.body.clientHeight) {
                windowHeight=document.body.clientHeight;
            }
        }
    }
    return windowHeight;
}


function setHeight() {
    if (document.getElementById) {
        var windowHeight=getWindowHeight();
        if (windowHeight>0) {
			// nur vergrößern, wenn Fenster kleiner ist
			if ((document.getElementById('footer').offsetHeight + document.getElementById('imgbox').offsetHeight + document.getElementById('header').offsetHeight + document.getElementById('left').offsetHeight) < windowHeight) {				
				document.getElementById('left').style.height = (windowHeight - document.getElementById('footer').offsetHeight - document.getElementById('imgbox').offsetHeight - document.getElementById('header').offsetHeight - 30)+'px';  // 30 = padding.bottom bei "left"
			}
        }
    }
}



window.onload = function() {
    setHeight();
}
window.onresize = function() {
    setHeight();
}

function opener(url,name,optionen) { 
  window.open(url,name,optionen);
}